This invention relates to uniform loading springs which may be included in a category with springs described generally as leaf springs, diaphragm springs, suspension springs or the like that form a cushion or loadbearing device. The springs of this invention may be employed in a wide variety of systems and can r eplace existing washers and springs such as wavy spring washers, curved spring washers, compression spri ngs and precision washers as well as lockwashers and the springs noted above. The instant springs are controlled by simple beam deflection.
In the past, a number of devices have been proposed that some similarity to the instant invention, but in every instance, there is a substantial distinction to be noted. In U.S. Pat. No. 2,179,575 to Hosking, entitled "Lock Washer," it is to be seen that the patentee described a device having a plurality of projections or locking elements which project from opposite sides of the washer body, and it is to be realized that such projections may include corners or edges that define sharp work e ngagi ng co rners o r edges that adapted to firmly embed themselves within the surface of the work piece, such as a screw head or nut. In other words, Hosking encourages his lock washer to engage the adjacent member, such as the underside of a screw head or a nut, in a scraping or scarring manner, so as "to effectively secure the nut against retrograde movement."
As will be seen, an object of this invention is to provide springs which have unlimited versatility, providing uniform spring loading, compression and flexibility under variable environmental conditions, without damage to adjacent members. My springs are designed with the objective of minimizing friction and overheating, shear, stress, fatigue or deformation, reducing noise levels, and damping oscillations or vibrations. Another objective is to reduce weight and bulk and enhance load capacity compared to existing springs employed for comparable jobs.
Existing lockwashers are typically loaded at one or sometimes several points, which causes shearing, scarring or other damage to the screw or base of the metal. If washers are used on both sides of the ordinary lockwasher, however, there is a tendency to loosen under vibration. Thus, another object of this invention is to prevent such vibrations, while avoiding undesirable qualities such as metal fracture, scarring and chipping. This makes my invention most valuable in "clean rooms."
Many spring systems and designs have failed because of lack of uniform loading and maintenance of alignment in many areas, such as bearings and optical precision instruments, due to temperature changes, stress, humidity, atmospheric pressure and other environments that may cause critical variations. In bearing designs proper alignment and adjustment of the ball track is very important to prevent skidding and noise and to increase beari ng life. In optical and other precision instruments, such as those employed in outerspace, maintenance of uniform loading, provision for expansion and contraction, reduction of stress, prevention of deformation, damping of vibrations or oscillations are vital to proper and successful performance.
Presently available wavy washers cannot be fabricated for sensitive uniform loading because of their configuration. The wavy portion on each contact segment is not equal and has a different spring rate. Twisting taking place on each contact segment causes undue stress which does not permit the material to return to its original position. This may be considered to be based upon structural fatigue. Belleville spring washers have similar problems because of buckling. Deformation or fracture of the spring can destroy the entire system in which it is employed.